[PATCH net] net: atlantic: keep rings across suspend/resume

[Lorenz Brun]

The rings are order-6 allocations which tend to fail on suspend due to
fragmentation. As memory is kept during suspend/resume, we don't need to
reallocate them.

This does not touch the PTP rings which, if enabled, still reallocate.
Fixing these is harder as the whole structure is reinitialized.

Fixes: cbe6c3a8f8f4 ("net: atlantic: invert deep par in pm functions, preventing null derefs")
Signed-off-by: Lorenz Brun <lorenz@xxxxxxxx>
---
 drivers/net/ethernet/aquantia/atlantic/aq_main.c     |  4 ++--
 drivers/net/ethernet/aquantia/atlantic/aq_nic.c      |  7 ++++---
 drivers/net/ethernet/aquantia/atlantic/aq_nic.h      |  2 +-
 drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c |  4 ++--
 drivers/net/ethernet/aquantia/atlantic/aq_vec.c      | 10 ++++++++++
 5 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_main.c b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
index c1d1673c5749..cd3709ba7229 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_main.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
@@ -84,7 +84,7 @@ int aq_ndev_open(struct net_device *ndev)
 
 err_exit:
 	if (err < 0)
-		aq_nic_deinit(aq_nic, true);
+		aq_nic_deinit(aq_nic, true, false);
 
 	return err;
 }
@@ -95,7 +95,7 @@ int aq_ndev_close(struct net_device *ndev)
 	int err = 0;
 
 	err = aq_nic_stop(aq_nic);
-	aq_nic_deinit(aq_nic, true);
+	aq_nic_deinit(aq_nic, true, false);
 
 	return err;
 }
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
index fe0e3e2a8117..a6324ae88acf 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
@@ -1422,7 +1422,7 @@ void aq_nic_set_power(struct aq_nic_s *self)
 		}
 }
 
-void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
+void aq_nic_deinit(struct aq_nic_s *self, bool link_down, bool keep_rings)
 {
 	struct aq_vec_s *aq_vec = NULL;
 	unsigned int i = 0U;
@@ -1433,7 +1433,8 @@ void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
 	for (i = 0U; i < self->aq_vecs; i++) {
 		aq_vec = self->aq_vec[i];
 		aq_vec_deinit(aq_vec);
-		aq_vec_ring_free(aq_vec);
+		if (!keep_rings)
+			aq_vec_ring_free(aq_vec);
 	}
 
 	aq_ptp_unregister(self);
@@ -1499,7 +1500,7 @@ void aq_nic_shutdown(struct aq_nic_s *self)
 		if (err < 0)
 			goto err_exit;
 	}
-	aq_nic_deinit(self, !self->aq_hw->aq_nic_cfg->wol);
+	aq_nic_deinit(self, !self->aq_hw->aq_nic_cfg->wol, false);
 	aq_nic_set_power(self);
 
 err_exit:
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
index ad33f8586532..f0543a5cc087 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
@@ -189,7 +189,7 @@ int aq_nic_get_regs(struct aq_nic_s *self, struct ethtool_regs *regs, void *p);
 int aq_nic_get_regs_count(struct aq_nic_s *self);
 u64 *aq_nic_get_stats(struct aq_nic_s *self, u64 *data);
 int aq_nic_stop(struct aq_nic_s *self);
-void aq_nic_deinit(struct aq_nic_s *self, bool link_down);
+void aq_nic_deinit(struct aq_nic_s *self, bool link_down, bool keep_rings);
 void aq_nic_set_power(struct aq_nic_s *self);
 void aq_nic_free_hot_resources(struct aq_nic_s *self);
 void aq_nic_free_vectors(struct aq_nic_s *self);
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c b/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
index 43c71f6b314f..1015eab5ee50 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
@@ -390,7 +390,7 @@ static int aq_suspend_common(struct device *dev)
 	if (netif_running(nic->ndev))
 		aq_nic_stop(nic);
 
-	aq_nic_deinit(nic, !nic->aq_hw->aq_nic_cfg->wol);
+	aq_nic_deinit(nic, !nic->aq_hw->aq_nic_cfg->wol, true);
 	aq_nic_set_power(nic);
 
 	rtnl_unlock();
@@ -426,7 +426,7 @@ static int atl_resume_common(struct device *dev)
 
 err_exit:
 	if (ret < 0)
-		aq_nic_deinit(nic, true);
+		aq_nic_deinit(nic, true, false);
 
 	rtnl_unlock();
 
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
index 9769ab4f9bef..3b51d6ee0812 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
@@ -132,6 +132,16 @@ int aq_vec_ring_alloc(struct aq_vec_s *self, struct aq_nic_s *aq_nic,
 	unsigned int i = 0U;
 	int err = 0;
 
+	if (self && self->tx_rings == aq_nic_cfg->tcs && self->rx_rings == aq_nic_cfg->tcs) {
+		/* Correct rings already allocated, nothing to do here */
+		return 0;
+	} else if (self && (self->tx_rings > 0 || self->rx_rings > 0)) {
+		/* Allocated rings are different, free rings and reallocate */
+		pr_notice("%s: cannot reuse rings, have %d, need %d, reallocating", __func__,
+			  self->tx_rings, aq_nic_cfg->tcs);
+		aq_vec_ring_free(self);
+	}
+
 	for (i = 0; i < aq_nic_cfg->tcs; ++i) {
 		const unsigned int idx_ring = AQ_NIC_CFG_TCVEC2RING(aq_nic_cfg,
 								    i, idx);
-- 
2.44.1